Visa Interview Questions, Process, and Tips for Freshers

Interview preparation tips for other job seekers - Go through the problems keenly and ask necessary questions.

Round: Test
Experience: 4 Coding questions on Hackerrank platform, one and half hour time. I am not going to reveal the questions here, but one was a basic binary tree implementation and the other three were algorithmic and mathematical problems. They were kinda hard to solve in an hour and half. I could do only 1 and half of the other one. I got 115/300 points on that. I was one of the 16 people selected for the interview.
Tips: It all depends on how well you can focus on the test day. Just practice a lot on hackerrank.
Duration: 1 hour 30 minutes
Total Questions: 4

Round: Technical Interview
Experience: The first two questions I was able to do fast enough. I was also asked a few questions on my resume and coding-related internship. The last one, I showed an O(n*n) algorithm first and then modified it to O(n). Around 45 minutes.
Tips: Be thorough on the coding part in your resume. Think out aloud!

Round: Technical + HR Interview
Experience: Just a few normal questions regarding my projects and my favorite course and it's application to Visa. 15 minutes.
Tips: Once again, be thorough on your resume.

Round: HR Interview
Experience: Once again a normal round, just random questions as to whether I am interested and good enough in communication. 15 minutes.
Tips: Don't get shaken. Be ready for all kinds of questions. Especially about Visa relation to what you do

Skills: Smart Coding
College Name: IIT Madras

Round: Test
Experience: The test was on hackerrank.
Tips: * Fast coding and problem solving required
* Time crunch
* The test is valued a LOT in the hiring process
Duration: 120 minutes
Total Questions: 4

Round: Technical Interview
Experience: Question 1 : He tried to take the discussion to web based technologies to which I straightly told I don’t know. Not sure if that was a good decision. Nevertheless, he went over my resume a lot of times and asked about various projects.
Question 2 : Discussed the various projects related to it.
Question 3 : He asked this question because I had worked on django during my FB internship. I proposed a tree based structure. xyz.com/a/b/c ---> b is child of a, c is child of b.

Question 4 : Next he moved to a very interesting question. Given a simple text editor, I want to facilitate autocomplete feature. We discussed about syntactic methods using language specific keywords. I suggested a trie based implementation which he liked. Later he asked me to improve and redirected me to using scope of the variables, and grammar of the language. We discussed about all the steps I did in language translators lab (macrojava -> minijava -> typechecking -> miniIR -> microIR -> miniRA ->Mips) where we built a Java compiler in Java. We later hopped back to original question and I suggested that we can use grammar to to store multiple (nested kind of) tries for different scope. He asked me how would I define “scope”. He gave me a scenario which helped me come up with the nested trie structure
int a;
{
int b;
{
int c; //a b c can be used
}
{
int d; //a b d can be used
}
}
He then asked me details of how I would code. I said we could use the respective visitors and maintain the current trie root for scope. He liked it but I missed at 2 places :
1. He asked me about token generation used in a compiler and I said flex and bison. I was expected to elaborate a bit.
2. He asked me how the grammar is generated and how the visitors are invoked. I couldn’t explain properly because I was not thorough with it.
Tips: * Keep smiling in the interviews.
* My interviewer had hopped from Microsoft to Visa. We had a short detailed discussion on how the transition was and what drove him to do that.
* It’s always good to know about the company to pick up interesting discussions, read up latest articles and news
* The interviewers want to see if you are passionate about what they are building. Their PPT (Pre Placement Talk) was also focussed majorly on the technologies they are building.
* If you take a question in a direction, make sure you are very very thorough with it. I took it in the direction of compilers, but couldn't make the transition seamlessly because I wasn't thorough with a lot of things (like token generation, visitor invocation).
* Not sure if telling upfront that you don't know about web technologies when you are applying for a profile that might need it is a good idea or not.


Round: Technical Interview
Experience: I think he was a senior person and spoke very passionately about the work that is happening in visa Bangalore office.

Question 1 : I said maybe I should have learnt a little about web based technologies. I think he was looking for a more generic answer.
Question 2 : I went ahead with calculating the expected score where my score random variable = 1 with probability p, and 0 with probability (1-p). I conditioned that expected score of game1 > game2 which would give me the range of p. I goofed up the equations twice but he said he liked my approach and I was just there

Question 3 : I suggested building a graph where a node is a word and an edge means a transition, and then performing BFS. He said that was obvious and that he was more interested in knowing how I build the graph. I suggested a method to reduce the number of string comparisons by storing a count vector with each word. Count vector is a 26 length vector where count[i] = number of times that letter occurs in the word. I would do string comparison to identify neighbours only if the difference in count vectors in 2. Eg, cot = cat - a + o. String comparison is still needed because of false positives. Eg, oct = cat - a + o but cat -> oct is not a valid transition. He liked my approach and asked me to code, discussed the complexity.
Tips: * Don't be naive around a senior engineer. Be confident.
* Explain your approach before going ahead solving it. I missed that in Q1 and for a long time he didn't know what I was heading towards.
* Write clean code, practice coding on paper to make sure you write compilable code. Shabby code is a turn off.
* Show passion for the company you are applying for.

General Tips: * Be friendly and keep smiling.
* Know about the company, well in detail. Recent news, articles, acquisitions, organisational changes, new offices, new product, etc.
* Know about the volume the company handles, certain mind boggling figures, what the company *does not* do
* If you are introducing yourself as an expert in a certain field, be prepared for questions like "How will you contribute to our company with your expertise" type of questions.
* Be very very thorough with every single thing you write on your resume. A small point you weren't sure about might become the basis of your whole interview. Don't write things you are unsure of, or have worked very little on.
Skill Tips: * I think I didn’t take Visa very seriously. I was assuming they won’t take a undergrad and they won’t take me because I have 0 knowledge in web based technologies. I might have acted a little cocky.
* They had nice pie diagrams which shows that they had done thorough research about each and every candidate based on resume and the coding test.
* They value the coding test a lot.
* Be very thorough with the projects you write on resume. They will give you a problem which won't be straightforward and will map onto one of your course projects. You are expected to do the mapping seamlessly. Every bit of the discussion you have with the interviewer can be your next problem.
* Brush up on web based technologies if you can.
* There will be a HR round as well if you clear the technical interviews.

Skills: Maths(esp Probability), Design, Passion, Web Technologies, Technical Skill And Speaking Skill, Coding Skills
College Name: IIT Madras
Motivation: * Been the leader since more than half a century, been through the technological revolution.
* Revolutionising payments architecture. Building something of greatest need, so elegant and optimised, yet producing such consistent performance.
* Keeping up with the need of the generation by introducing features which are brand new. Eg, “all-purpose credit card”.
* Loved their PPT (Pre Placement Talk). Volume of the data and processing is IMMENSE. Billions of transactions in a year voluming up to trillions. More than 200 countries in the world --> these stats are HUGE.
* Fraud detection is a space I would have loved to work on given that I come from a Data Mining background.

Funny Moments: Chucked out before HR round :P

Round: Technical Interview
Experience: majorly focused on the projects I had done as part of my curriculum. Then some basic coding stuff where the interviewer was mainly trying to see the approach. Some questions related to sorting techniques.
He was also interested in the real time projects that I worked on during my interns at Amazon. So I was asked about all that I did there and then some questions on spring framework and dependency injection (amazon intern project related stuff).

Round: Technical Interview
Experience: Here the discussion started with OS and networking. General questions on race condition, semaphores, raid structure, deadlocks as well as network layer, data-link layer and transport layer (One who is well acquainted with all the basics of subject can easily answer them all). Some machine learning discussion on classifiers, Artificial Neural Networks, and genetic algorithms as well as assembly language programming. A code for a problem which could be solved using BST and then optimizing it.

Round: HR Interview
Experience: First the interviewer started with explaining kind of work Visa does and their plans for the technology hub they are opening up in Bangalore and my interests and all. Then some questions related to writing POJO(Plain Old Java Objects) classes and tests for the code (unit tests, integration tests) based on what I mentioned in my resume as part of my intern project. Some aptitude questions and programming stuff again and then about Object Oriented Programming (OOPs) concepts.

College Name: NA

Round: Test
Duration: 120 minutes
Total Questions: 42

Round: Test
Experience: There was a test for VISA which had following sections:
Assessment Composition:
1. Coding Skills: 2 Questions - Very simple problems - 30 marks total
2. Programming: 10 Questions - Simple Java Questions --Access modifiers, inline function, Red black tree, heap
3. Machine Learning Hadoop MCQ: 6 Questions You can't answer a single question if ML/BigData is remote-land for you.
4. Networking MCQ: 6 Questions - Again basics. Data layer questions. IP class basic question, fields in ethernet header.
5. Operating System: 6 Questions - Memory management mostly
6. Infrastructure: 6 Questions - Real life scenarios - server client questions.
7. Application Security: 6 Questions
Duration: 120 minutes
Total Questions: 42

Round: Interview
Experience: Questions from all CS subjects including coding
Tips: They shortlisted 29 students for the final interviews on Day 1 Slot 1.
There were 2 rounds of technical interview and 1 interview.

General Tips: Do’s
1)      Start right from August 
2)      Prepare basics of subjects
3)      Try to code using pen and paper
4)      Code as many problems as you can from all domains with only 1 language (C/C++/Java)
5)      Keep a friend with you at all times during interviews. If you are selected for more than 1 companies in 1 slot, ask your friend to manage your interview schedules given he knows your priorities. I was not in a position to attend more than 2 interviews in the same slot.
Don’ts
1)      Don’t lose hope if you are not shortlisted for your dream company or any company of your choice because being an IITian you have large number of better choices and which would fit in your profile better.
2)      Don’t argue with the interviewers and never pretend that your are over smart in a given domain.
3)      Do not take HR rounds lightly even if you are sitting for CS companies.
Skills: C++
College Name: IIT Kanpur
Motivation: Role of my interest